Abstract
The traditional method to measure the W Boson mass at a hadron collider (more precisely, its ratio to the Z boson mass) utilizes the distributions of three variables in events where the W decays into an electron or a muon: the charged lepton transverse momentum, the missing transverse energy and the transverse mass of the lepton pair. We study the putative advantages of the additional measurement of a fourth variable: an improved phase space singularity mass. This variable is statistically optimal, and simultaneously exploits the longitudinal- and transverse-momentum distributions of the charged lepton. Though the process we discuss is one of the simplest realistic ones involving just one unobservable particle, it is fairly nontrivial and constitutes a good “training” example for the scrutiny of phenomena involving invisible objects. Our graphical analysis of the phase space is akin to that of a Dalitz plot, extended to such processes.
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ArXiv ePrint: 1106.0396
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Open Access This is an open access article distributed under the terms of the Creative Commons Attribution Noncommercial License (https://creativecommons.org/licenses/by-nc/2.0), which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.
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De Rújula, A., Galindo, A. Measuring the W-Boson mass at a hadron collider: a study of phase-space singularity methods. J. High Energ. Phys. 2011, 23 (2011). https://doi.org/10.1007/JHEP08(2011)023
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DOI: https://doi.org/10.1007/JHEP08(2011)023